Striking attachment for clocks



March '24, 1936. F, w HADERMAN 2,034,945

STRIKING ATTACHMENT FOR CLOCKS Filed Nov. '7, 1955 E15 11' INVENTOR Y Iml ATT NEYS.

Patented Mar. 24, 1936 UNITED STATES PATENT 3 Claims.

This invention relates to improvements in striking attachments forclocks.

The principal object of the invention is to provide means for thestriking of a gong of a clock, either electric or spring driven.

A further object is to provide means whereby the striking mechanism isthrown out of alignment with the moving clock parts except at the properinterval.

A further object is to produce a device which is simple in constructionand one which may be readily applied to any clock without materiallyaltering its construction.

A still further object is to produce a device which is economical tomanufacture.

Other objects and advantages will be apparent during the course of thefollowing description.

In the accompanying drawing forming a part of this specification and inwhich like numerals are employed to designate like parts throughout thesame,

Fig. 1 is a front elevation of my improved striking mechanism,

Fig. 2 is an end elevation of Fig. 1,

Fig. 3 is a view similar to Fig. 1, showing the parts ready to move intostriking position,

Fig. 4 is an end elevation of Fig. 3,

Fig. 5 is a top plan view of the invention,

Fig. 6 is a fragmentary detail view of the actuator lever.

Electric clocks usually employ a buzzer system to indicate timeintervals. In some instances gongs are arranged to strike the hours.These arrangements, however, are very complicated and add materially tothe cost of the clock. Applicant has devised a simple mechanism whichmay be attached to any clock, particularly electric clocks, which willstrike the hours.

In the accompanying drawing wherein for the purpose of illustration isshown a preferred embodiment of my invention, the numeral 5 designatesthe clock frame from which protrudes a shaft 6, upon which a disc I ispositioned. This disc carries striker pins 8. The shaft 6 may be anyrotating part of the clock which travels with sufficient speed toproduce the desired result. The numeral 9 designates the minute shaft ofthe clock upon whose hour sleeve is mounted a snail cam ll. Mounted uponthe frame 5 is a rack l2 pivoted as at l3, which has ratchet teeth M. Apin l6 carried by the arm 12 is adapted to engage the snail cam I l aswill be later described.

The numeral l1 designates a rocker shaft having a hammer 20 securedthereto, which is capable of striking a gong 25. This shaft I! haspivotally mounted thereon, an actuator lever I8 which is biased with aflat spring l8a. and has a tail portion for engagement with the strikerpins 8 and a head portion 2|. The head portion is provided with abeveled surface 22 adapted to be contacted by the beveled tail portionof a firstclass lever 24. A spring 26 tends to keep the rocker shaft I!turned in a counter-clockwise direction. An arm 2'! is secured to therocker shaft 11 and has pivoted thereto a gathering pawl 28, the nose ofwhich engages the teeth M of the rack I2. The member 24 whichconstitutes a hold-back pawl also has a nose 29 extending under the pawl28 and adapted to engage the teeth l4 at certain intervals. A bell cranklever 3| is pivoted as at 32 to the case 5 and has its lower extremityin the path of movement of a pin 33 carried on an arm 33a driven by theminute shaft 9. The opposite end of this bell crank lever has a lug 34which overlies the lever 24.

The operation of my device is as follows:

Assuming that the parts are in the position of Figs. 1 and 2, therotation of the shaft 6 will cause the pins 8 to revolve, but they willbe out of engagement with the tail of the actuator lever I8 for thereason that the actuator lever is being held in tipped position of Fig.2 by the tail of the hold-back pawl 24. As the minute shaft 9 rotates,the pin 33 will gradually move the lower end of the bell crank lever 3!until the lug 34 moves against the tail of the pawl 24, which actionwill cause the nose 29 of the pawl 24 which underlies the gathering pawl28 to raise the nose of the hold-back pawl out of engagement with theteeth [4 of the rack 12. As soon as this occurs the rack will fall bygravity until the pin [6 engages a step of the cam H. The end of thebell crank lever will then be moved into engagement with the headportion 2! of the lever l8 to hold the same in the position of Fig. 3,at the same time elevating the nose of the holdback pawl. As soon as thepin 33 passes the end of the bell crank lever 3|, the bell crank leverwill move back to the position of Fig. 1, thus releasing the lever 18and allowing it to move into the position of-Fig. 4 to be engaged by thepins 8. As the shaft 6, carrying these pins, is rotating, the engagementof the pins with the lever will cause a rocking action of the shaft 11,each time one of the pins engages the lever l8, which will cause thehammer 28 to strike the gong 25. At each actuation of the rocker shaft,the link 21 will work the pawl 28 over the teeth l4 and will advance therack !2 one notch for each stroke of the gong. The nose 29 of the pawl24 will prevent retrograde movement of the rack l2. As soon as the rackl2 has reached a point where the nose 29 of the pawl 24 falls off of theteeth, upward movement of the end of the pawl will cause its tail toengage the cam surface 22 of the actuator lever and move it from theposition of Fig. 4 to the position of Fig. 2. Then the parts will be intheir inoperative position and will not operate again until the nexthour.

It is to be understood that the form of my invention herewith shown anddescribed is to be taken as a preferred example of the same and thatvarious changes relative to the material, size, shape and arrangement ofparts may be resorted to without departing from the spirit of theinvention or the scope of the subjoined claims.

Having thus described my invention, I claim:

1. In combination with a time mechanism having minute and hour spindles,a snail cam carried by the latter, a pivotally mounted rack governed inits pivotal movement by the snail cam,

' a constantly rotating member driven by the clock mechanism, gatheringand hold-back pawls engageable with the rack, a lever intermittentlyactuated from the minute spindle, a rock shaft, an arm pivotally mountedon the rock shaft for movement into and out of obstructing position withrespect to said constantly rotating member, the lever being engageablewith the arm to retain it in its unobstructing position, the holdbackpawl being likewise engageable with the arm to retain it in itsunobstructing position, the rock shaft having a gong actuating means,the gathering pawl being operatively connected with the rock shaft, thehold-back pawl being movable to arm releasing position by the lever andengageable with the rack after the lever actuating operation of theminute spindle.

2. In combination with a time mechanism having minute and hour spindles,a snail cam carried by the latter, a pivotally mounted rack governed inits pivotal movement by the snail cam, a constantly rotating memberdriven by the clock mechanism, gathering and hold-back pawls engageablewith the rack, a lever intermittently actuated from the minute spindle,a rock shaft, an arm pivotally mounted on the rock shaft for movementinto and out of obstructing position with respect to said constantlyrotating member, the lever being engageable with the arm to retain it inits unobstructing position, the holdback pawl being. likewise engageablewith the arm to retain it in its unobstructing position, the rock shafthaving a gong actuating means, the gathering pawl being operativelyconnected with the rock shaft, the hold-back pawl being movable to armreleasing position by the lever and engageable with the rack uponcompletion of the lever actuating operation, the lever having a presserfoot engageable with the hold-back pawl to release it from the arm andlikewise having a member engageable with the corresponding member on thearm to retain the latter in its unobstructing position when releasingthe hold-back pawl, the lever during those periods when it is notactuated by the minute spindle dropping by gravity to a position free ofthe hold-back pawl or the arm.

3. In combination with a time mechanism having minute and hour spindles,a snail cam carried by the latter, a pivotally mounted rack governed inits pivotal movement by the snail cam, a constantly rotating memberdriven by the clock mechanism, gathering and hold-back pawls engageablewith the rack, a lever intermittently actuated from the minute spindle,a rock shaft, an arm pivotally mounted on the rock shaft for movementinto and out of obstructing position with respect to said constantlyrotating member, the lever being engageable with the arm to retain it inits unobstructing position, the holdback pawl being likewise engageablewith the arm to; retain it in its unobstructing position, the rock shafthaving a gong actuating means, the gathering pawl being operativelyconnected with the rock shaft, the hold-back pawl being movable to armreleasing position by the lever and engageable with the rack uponcompletion of the lever actuating operation, the lever having a presserfoot engageable with the hold-back pawl to release it from the arm andlikewise having a member engageable with the corresponding member on thearm to retain the latter in its unobstructing position when releasingthe hold-back pawl, the lever during those periods when it is notactuated by the minute spindle dropping by gravity to a position free ofthe hold-back pawl or the arm, the constantly rotating member consistingof a disk with uniformly spaced pins on one face thereof and the leverhaving a tail portion movable into and out of the path of said pin inthe extremes of its pivotal movement.

FRANK W. HADERMAN.

